Before 1909, American pop songs could be romantic and even coy about sex. But none were so explicit about adultery as "I Love My Wife — But Oh! You Kid!" about a married man named Jonesy and the young lass who catches his eye.
“I Love, I Love, I Love My Wife—But Oh! You Kid!” had captured the zeitgeist, that it was a sign—the sound—of the times. It incited countless newspaper editorials, fulminating sermons by preachers, and at least one fatal shooting.
Even if the cat-calling implication weren't there, addressing a lady one doesn't know as "Oh, you!" would be bad manners in 1909. Kind of like, "Oi, sweetheart!" is now.
Her expression seems to indicate fear? I think Mr. True is picking up on her discomfort. Not that it should warrant a beating, but Mr. True's reactions are often hyperbole.